Black Corydoras Schultzei schooling behavior

[Greg Y]

Hi there, first post

I have 6 baby Black Corydoras Schultzei that I won at a local fish auction in my 4'x2' footprint 110gal. planted community tank.

They seem happy and healthy but haven't displayed any schooling behavior yet, they seem scattered all over the tank.
I contacted the breeder and he agreed to sell me 6 more.

Is this a good idea, 12 vs 6, and will this encourage them to school more?
PS,
they share the bottom of the tank with 4 Bolivian Rams

[Coryman]

The reason most fish 'shoal' together is in defense of possible predatory activity. Also it is a numbers thing. To me 6 fish would not constitute a 'shoal' nor would they react as such. A larger group 20 or 30 would make up a small 'shoal'. However in a safe environment the instinct to group together is weaker and then the only time that they group is around a food source.

I have two tanks with C. hastatus, one has a breeding group of 6 and in the other there are 30, the 30 will often shoal together in various sizes groups, but the 6 hardly ever.

The tank size will also have an effect on how the fish will react.

Ian